ECG Directory

Welcome to this interactive ECG course.

Although it is one of the oldest paraclinic exams, dating back to the late 19th century, the ECG is still of crucial clinical use. This examination often still poses problems of interpretation to the medical practitioner.

This course aims to help the student, the practicing physician and even the trained cardiologist to improve his knowledge in electrocardiography. It consists of 250 traces of varying complexity with a description of each one by experts. This allows the reader to compare his analysis with that of the experts. In addition, the areas of interest of the ECG can be activated to be clearly highlighted.

We hope that these plots will be useful to readers and will improve their knowledge.

The ECGs are available sorted by keywords and categories.

ECG 145

ECG 145


Basic rhythm

Sinus rhythm, regular at 50 bpm.

P waves


PR interval

Shortened, practically negligible (85 ms) with delta wave.


Prolonged (130 ms), slurred or notched in its inital portion. Normal axis.

ST segment, T waves

Widespread changes.

QT interval



Short PR interval. ∂ wave.
Normal QRS axis.


Wolff-Parkinson-White syndrome with pre-excitation of the right anterior ventricle, close to the conduction pathways.


The inital deformation of the QRS wave corresponds to a delta wave whose normal axis, and the negative polarity in V1, allow the pre-excitation to be located in the right anterior region, close to the normal conduction pathways. The changes in the terminal phase are due to the abnormal activation of the ventricles.




Reading level

2 / 3